Integration Testing on Swarm
IT on Swarm allows you to execute integration test in parallel across a Docker Swarm cluster
Architecture
Master service
- Works as a funker caller
- Calls a worker funker (
-worker-service
) with a chunk of -check.f
filter strings (passed as a file via -input
flag, typically /mnt/input
)
Worker service
- Works as a funker callee
- Executes an equivalent of
TESTFLAGS=-check.f TestFoo|TestBar|TestBaz ... make test-integration-cli
using the bind-mounted API socket (docker.sock
)
Client
- Controls master and workers via
docker stack
- No need to have a local daemon
Typically, the master and workers are supposed to be running on a cloud environment,
while the client is supposed to be running on a laptop, e.g. Docker for Mac/Windows.
Requirement
- Docker daemon 1.13 or later
- Private registry for distributed execution with multiple nodes
Usage
Step 1: Prepare images
$ make build-integration-cli-on-swarm
Following environment variables are known to work in this step:
BUILDFLAGS
DOCKER_INCREMENTAL_BINARY
Note: during the transition into Moby Project, you might need to create a symbolic link $GOPATH/src/github.com/docker/docker
to $GOPATH/src/github.com/moby/moby
.
Step 2: Execute tests
$ ./hack/integration-cli-on-swarm/integration-cli-on-swarm -replicas 40 -push-worker-image YOUR_REGISTRY.EXAMPLE.COM/integration-cli-worker:latest
Following environment variables are known to work in this step:
DOCKER_GRAPHDRIVER
DOCKER_EXPERIMENTAL
Flags
Basic flags:
-replicas N
: the number of worker service replicas. i.e. degree of parallelism.
-chunks N
: the number of chunks. By default, chunks
== replicas
.
-push-worker-image REGISTRY/IMAGE:TAG
: push the worker image to the registry. Note that if you have only single node and hence you do not need a private registry, you do not need to specify -push-worker-image
.
Experimental flags for mitigating makespan nonuniformity:
-shuffle
: Shuffle the test filter strings
Flags for debugging IT on Swarm itself:
-rand-seed N
: the random seed. This flag is useful for deterministic replaying. By default(0), the timestamp is used.
-filters-file FILE
: the file contains -check.f
strings. By default, the file is automatically generated.
-dry-run
: skip the actual workload
keep-executor
: do not auto-remove executor containers, which is used for running privileged programs on Swarm